1. Field of the Invention
This invention relates to the field of electronic devices, and more particularly, to power generators for electronic devices.
2. Description of the Prior Art
The uses of battery operated portable electronic devices like cell phones, hand held Personal Digital Assistants (PDA), MP3players, laptops and digital gaming devices are increasing every day in the modern world. Miniaturization has further revolutionized their design and portability. All these devices rely on a secondary power source from rechargeable batteries installed in them for portability. Rechargeable batteries with longer life and improved performance in respect of standby time and talk (or use) time, charging cycles are presently available. However, despite all such technological advances, it is a common and frustrating experience with the users of these devices, particularly the travelers and tourists, who are often cut-off from any primary power source to recharge the battery, the moment the charge in the battery flattens out the device is rendered useless.
Attempts have been made to solve this problem by harvesting solar energy through solar panels installed in the device like cell phone.
U.S. Pat. Nos. 6,504.340 and 6,977,479 and also U.S. published patent applications U.S. 20030128010A1, U.S. 20040204179A1, U.S. 20050225281A1, U.S. 20050162121A1 and U.S. 20060212994A1 have all disclosed harvesting of solar energy to charge a cell phone battery.
However, such solar powered charging devices have their own drawbacks. Firstly, a traveler normally wishes to keep the phone inside his pocket or purse that does not get the sun ray to energize the solar charger or may be he is moving in a transport without any access to the sun ray and thereby fails to harvest solar energy. Secondly, a dual powered device adds to its size and thus goes against the current trend for miniaturization.
Portable recharging units using rechargeable or non-rechargeable AA or AAA batteries are also available in the market but are not convenient or cost effective, as they need frequent recharging or battery replacement with limited capacity to charge the device battery only 2-3 times.
The published U.S. patent application with publication No. 2006/0139000 A1 discloses a wrist worn battery charging system to charge or power batteries for devices like cell phones, PDAs, laptops, MP3 players comprising a permanent magnet adapted to move back and forth on rails, surrounded by copper coils attached to an electronic circuitry comprising a battery interface for filtering output pulses with connecting cable that can be plugged into the charging point of a portable device. The back and forth movement of the permanent magnet caused by the wrist movement of the user helps to generate power in the surrounding coils through electromagnetic induction. While this appears to be the first attempt to harvest kinetic energy to generate electrical power for recharging hand held electronic devices, the present invention, as described herein, is a distinct improvement over the said prior art device that provides a pair of magnetic bumpers to ensure the oscillatory movement of a magnet within an induction coil even with small movement of the user carrying it which in turn ensures generation of steady output of electrical energy for recharging or powering a portable electronic device powered by a chargeable battery.